The Federal Aviation Administration is in close contact with Boeing as the company "continues its work on the automated flight control system on the 737 MAX".

The largest USA plane manufacturer has been dealing with a number of software program issues involving the jet that has been grounded since March previous year.

The aerospace giant had already halted production at its Puget Sound facility near Seattle, where the company builds the long-range 777 jet and other models, after announcing a two-week stoppage last month.

Boeing stated it does not anticipate the problems to impact its current forecast of a mid-year return to service for the aircraft. Boeing said the new software issues are not linked to a major anti-software system known as MCAS, which was the cause of both fatalities.